Rhenium(IV)–copper(II) heterobimetallic complexes: Synthesis, crystal structure and magnetic properties

Two Re(IV)–Cu(II) heterometallic complexes {(CuLα)[ReCl4(ox)]}n (where Lα = N-meso-5,12-Me2-7,14-Et2-[14]-4,11-dieneN4), 1, and (CuLβ)[ReCl4(ox)] (Lβ = N-rac-5,12-Me2-7,14-Et2-[14]-4,11-dieneN4N-rac-5,12-Me2-7,14-Et2-[14]-4,11-dieneN4), 2, were synthesized. The [CuL2+] macrocyclic cation is coordinated from above and below by [ReCl4(ox)]2− units through the chloro-ligands and creates a chloro-bridged heterometallic ReIV–CuII one-dimensional zig-zag chain. Compound 2 can be viewed as a heterobimetallic dinuclear unit, in which the Re(IV)-Cu(II) centers are linked by an oxalato bridge. The magnetic behavior of 1 and 2 has been investigated over the temperature range 1.8–300 K. Compound 1 behaves like a ferrimagnetic {Re(IV)–Cu(II)} bimetallic, one-dimensional chain with intrachain antiferromagnetic coupling. Compound 2 shows a weak antiferromagnetic interaction within the [Re(IV)–Cu(II)] unit along with a strong single-ion anisotropy, D(Re) = −63 cm−1.

Graphical abstractTwo Re(IV)–Cu(II) heterometallic complexes {(CuLα)[ReCl4(ox)]}n (where Lα = N-meso-5,12-Me2-7,14-Et2-[14]-4,11-dieneN4), 1, and (CuLβ)[ReCl4(ox)] (Lβ = N-rac-5,12-Me2-7,14-Et2-[14]-4,11-dieneN4N-rac-5,12-Me2-7,14-Et2-[14]-4,11-dieneN4), 2, were synthesized. The [CuL2+] macrocyclic cation is coordinated from above and below by [ReCl4(ox)]2− units through the chloro-ligands and creates a chloro-bridged heterometallic ReIV–CuII one-dimensional zig-zag chain. Compound 2 can be viewed as a heterobimetallic dinuclear unit, in which the Re(IV)–Cu(II) centers are linked by an oxalato bridge. The magnetic behavior of 1 and 2 has been investigated over the temperature range 1.8–300 K. Compound 1 behaves like a ferrimagnetic {Re(IV)–Cu(II)} bimetallic, one-dimensional chain with intrachain antiferromagnetic coupling. Compound 2 shows a weak antiferromagnetic interaction within the [Re(IV)–Cu(II)] unit along with a strong single-ion anisotropy, D(Re) = −63 cm−1.Figure optionsDownload full-size imageDownload as PowerPoint slide